ABSTRACT: The Interpersonal Reactivity Index (IRI) is a commonly used instrument for measuring individual differences in trait empathy. It is composed of the following four subscales: Perspective taking; fantasy; empathic concern; and personal distress. Previous studies have reported finding a positive relationship between psychological well-being and perspective taking, but little remains known about the association between psychological well-being and the other IRI subscales. Thereforein this study, we investigated the degree to which each IRI subscale could predict psychological well-being, which was measured using Ryff’s Psychological Well-Being Scales, in 119 Japanese undergraduate and graduate students (43 females, 76 males; mean age: 22 years; age range: 19 - 25 years). Regression analysis revealed that perspective taking positively predicted personal growth, purpose in life, and environmental mastery, while personal distress negatively predicted autonomy, environmental mastery, and self-acceptance. Neither fantasy nor empathic concern predicted psychological well-being. These results support those found in previous studies, and suggest that perspective taking, a cognitive component of empathy, plays an important role in the improvement of psychological well-being.